VELCADE™ (bortezomib) for injection is a small molecule proteasome inhibitor developed by Millennium Pharmaceuticals, Inc., (MPI) as a novel agent to treat human malignancies. VELCADE is currently approved by the US FDA for the treatment of multiple myeloma patients who have received at least 2 prior therapies and have demonstrated disease progression on the last therapy. VELCADE is a modified dipeptidyl boronic acid derived from leucine and phenylalanine; its chemical name is N pyrazinecarbonyl L phenylalanine L leucine boronic acid and has a molecular weight of 384.25 daltons.